Why would someone consider a position that seems like a step back?

I’m currently a staff engineer at a mid-sized company (600+ employees) with over 8 years of experience. Recently, I was approached for a principal engineer role at an AI startup that piqued my interest. After the initial screening call, they came back with an offer to proceed, but for a senior position instead.

Given the current market landscape, I understand that times are tough, but I already have a stable job, and my salary as a staff engineer is likely higher than what they would offer for a senior role. Frankly, I find it a bit disrespectful to receive such an offer, especially since they reached out to me rather than me applying. If they believe I’m not a suitable fit, I’d prefer a straightforward response.

So, I’d like to hear from recruiters: why make such an offer? And to fellow engineers: what would motivate you to accept a perceived downgrade in your career? Thankfully, I wasn’t laid off, so I’m not in a rush to make a move.